The HP4 answers the project studio owner’s needs for headphone distribution with professional specs in a small package at an affordable price. It accepts unbalanced 1/4" inputs& delivers 1/4" TRS out. The input can be stereo or mono (mono copies to both outs). It features 4-front panel headphone outs w/volume control, -98 dB noise floor, monitor MUTE, and is powered by an external wall mounted power supply.